Floodwater released from a hydroelectric dam has completely submerged a Cambodian village, turning it into a “silent waterworld”.

The new Lower Sesan 2 Dam has unleashed a deluge of water on Srekor, in the northern province of Stung Treng, according to California-based campaign group International Rivers.

More than 60 families have been forced to abandon their homes as floodwater levels have gradually risen around seven metres since the dam began operating in November.

“The thriving community of Srekor has become a silent waterworld,” International Rivers said in a statement, adding the village’s farms, temple, ancestral graves and fishing grounds had all been destroyed.

The 400-megawatt dam, a joint-venture between China’s Hydrolancang International Energy Company and Cambodia’s Royal Group is around 75 metres high and five miles long.

Part of China’s hydropower ambitions in the Mekong River region, it is aimed at generating electricity for Cambodia.

However, several environmental groups have issued stark warnings the project will have a devastating impact on fisheries and biodiversity.

Srekor resident Bong Kheun told Washington-based EarthRights International water levels were so high in the village, he was unable to find his home when he returned to collect belongings.

“I had tears in my eyes when I saw my flooded home and village,” he said. “Every time I think about my life before our village was flooded, I long to go back to that time.”

Cambodian Prime Minister Hun Sen has labelled those who have raised concerns about the dam “radical”, saying Cambodia needed to keep up with rising energy demand.

International Rivers estimates around 5,000 people, mostly from the region’s indigenous and ethnic minority groups, have been displaced during the project.

Hundreds of families from five villages have been moved by government officials to designated resettlement sites.

Around 10 families from Srekor had been relocated, although dozens more had chosen to stay behind.

A Stung Treng provincial authority spokesman said the floods were expected and that villagers could still approach authorities about resettlement and compensation.